Method of surface finishing articles



Dec. 15, 1936. w. RUPPERT METHOD OF SURFACE FINISHING ARTICLES Filed Oct. 11, 1935 FIG.,

FIG. 8.

FIG. 9.

INVENTOR 1.. W. RUPPE'RT 'Arramvsr Patented Dec. 15, 1936 "UNITED STATES v 2,064,322 METHOD oa sonmca mmsnme narrows Ladis W. Ruppert, Crani'ord, N. J., assignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application October 11, 1933, Serial No. 693,123

' 2 Claim.

in which either the customary die :block of the press or the ram head or both are provided with a special tool comprising a multiperforate block each of the perforations of which holds aspecial forming tool having a convex working surface.

In its simplest form such a tool may be thought of as a hardened steel ball or a short cylinder with a convexly curved working end. Such a block may contain a considerable number of such tools. A sheet of metal to befi'nished may be held between the working parts of the press and at each stroke will receive a plurality of indentations. By moving the sheet between strokes the indenta-v tion's will be'distributed irregularly thereover, the regular distribution of any one set of indentations becoming imperceptible in the chance controlled irregularity of distribution of successive sets.

Other objects and features of the invention will appear fromthe following detailed description of one embodiment thereof taken in connection with I the attached drawing wherein the same reference numerals are attached to identical parts in the several figures and in which Fig. 1 is a diagrammatic perspective broken view of the working ends of the die block and ram head of a conventional punch press with a tool adapted to carryout the method of the invention mounted on the die block; Fig. 2 is a detached perspective view partly broken away of a preferred form of the tool;

Fig. 3 is a similar view of a modified form; Fig. 4 is a detached perspective'view of anothe modified form v Fig. 5 is a detached broken view in side elevation of a third form;

Fig. 6 is a perspective of a piece of sheet metal before treatment:

Fig. 7 is a similar view of the piece partly treated;

Fig. 8 is a detached view in elevation of a fourth 50 form, and i 1 Fig. 9 is a detached view in perspective of a fifth form;

In practising the invention as hereindisclosed, Fig. 1 shows diagrammatically the ram head It! 55 and die block ll of a power driven punch press of any convenient and approved construction. A special tool block I2 is supported on the die block. A cooperating block l3 may be attached to the bottom face of the ram.

The tool block I2 is provided with a plurality of parallel vertical perforations |4.- In each perforation I4 is positioned a tightly fitting cylindrical member l5 having a convexly rounded upper working face l6 and a fiatbottom face IT. The cylindrical members I 5 may be hardened throughout or the faces l6 may be hardened and the rest of the members treated to have maximum toughness. Each member I5 is supported on its fiat face ll by the top surface l8 of the die block] I, and is given lateral support if necessary by the tool block l2.

In operation, a piece of metal l9 to be treated may be taken by one corner with a pair of tongs for example and laid on the tool faces 16. The press is then started and having been so adjusted beforehand that at the lowest position of the ram, the distance between the bottom face of the block l3 and the faces l6 isJessthan the thickness of the plate I 9, the under surface of the plate will be plurally indented by the members I5. ,As the ram head rises, freeing the plate l9, thelatter is turned and slid slightly and the next stroke of the ram produces another set of indentations.

The regular rows and columns of the second set of indentations will be irregularly related to those of the first set. A third set will lie irregularly with respect to the first two sets. This procedure is continued until in the judgment of the operator, the desired effect 20 has been produced. The positioning of the internally regular identical successive sets of indentations relatively to each other is thus entirely haphazard on chance controlled. I

If it is desired to produce the effect-upon both sides of the plate l9, the block l3 may be replaced by a tool similar to that on the die block,

whereby both faces of the plate will be indented simultaneously.

Fig. 3 discloses a modified form of tool in which the cylindrical-members IS 'in the block I! are replaced by hardened spheres 2| which are supported on a hardened plate 22.

. Fig. 4 discloses another modified form of tool in which a block i2 is formed with integral rounded projections 23 which may be hardened to serve the'purpose of the faces I6. Or the projections may be formed by welding or otherwise fastening independently preformed knobs upon a plane I faced block.

In any one of the forms disclosed, the working faces l6 of the indenting tool are usually substantially equidistant at their apices from the meeting face of the block l3, but in some cases may be made to vary slightly in this respect to enhance the resulting appearance of irregularity of the indentations.

in an appropriate rolling mill diagrammatically.

indicated in Fig. 5, such as is customarily used for rolling operations, to coact with a correspending smooth roll 25, or the, smooth roll 25 may be replaced by a roll similar to the roll 24 when it is desired to indent simultaneously both faces of a plate passed therebetween.

In this last arrangement it'is also possible to operate on a cylindrical article if the roll 25 be so mounted that the article may he slipped over the roll, as for example by making one bearing of the roll 25 removable.

A fourth form of tool may be composed of a bundle of such cylinders as those shown at IS in Fig. 1 held immovably together by a tight band 26 as shown in Fig. 8; and fifth form may be made by enclosing a plurality of balls 2| in a rigid tray 27! as shown in Fig. '9, the tray-being so proportioned that the balls are held rigidly against relative displacement.

The embodiments of the apparatus and the modes of practising the invention herein disclosed are illustrative merely and may be modified and departed from in many ways without departing from the spirit and scope of the invention as pointed out in and limited solely by the appended claims.

What is claimed is:

1. An article having a simulated hand hammered ornamental surface finish comprising several pluralities of indentations impressed into a surface of the article, the indentations of each plurality being regularly arranged with respect,

to each other and each plurality being positioned at haphazard with respect to each other plurality and each plurality overlapping at least in part at least one other plurality.

2. A method of treating the surface 01' a malleable article to produce thereon a simulation of a hand hammered finish which comprises the steps of simultaneously impressing a regularly arranged plurality of indentations into a portion of the surface of the article and subsequently impressing a second identically arranged plurality of indentations into a part of the same portion of the surface of the article, the second 'plurality of indentations as a whole being irregularly positioned at haphazard with respect to the first plurality whereby an ornamental surface finish is produced on the article having the irregular appearance of a hand hammered finish.

LADIS W. RUPPERT. 

